The creator of hit TV show Heroes has apologised to fans in the US for a slow start to the second series.Tim Kring admitted to Entertainment Weekly that mistakes had been made on the choice of storylines, but promised to get the show back on track. The second series has seen falling ratings in the US, where the programme is now eight episodes in. Viewers in the UK can see the conclusion of the first series on BBC Two on 5 December. 'Mistake'The superhero show, starring Hayden Panettiere and Masi Oka, was the top-rated new drama in the US last year. But recent programmes have seen audiences slip away - with one recent episode placing 30th in the overall ratings. The drop-off has been attributed to an influx of new characters and sluggish story-telling. Kring admitted the pace had been too slow. "We assumed the audience wanted season one - a build up of intrigue about these characters and the discovery of their powers. They wanted adrenaline. "We made a mistake - we took too long to get to the big-picture story," he added.